Voltage stabiliser for electrical energy transportation and distribution applications

ABSTRACT

Voltage stabiliser for electrical energy transportation and distribution applications, which consists of one or several electromagnetic devices of transformer type which, at discrete intervals, regulates the output voltage that reaches the consumer, taking the form of a transformer with a dual or quadruple primary winding and a simple secondary winding, the simple winding being able to be positioned before or after the parallel branch, the performance of the equipment remaining the same.

OBJECT OF THE INVENTION

[0001] The herein descriptive specification refers to an InventionPatent application, in relation to a voltage stabiliser for electricalenergy transportation and distribution applications, the aim of which isto enable its use as a voltage stabiliser at different electrical energyvoltage levels, capable of being installed in single phase and threephase networks, consisting of one or several electromagnetic devices oftransformer type and which, in incremental steps, regulates the outputvoltage which reaches the consumers.

FIELD OF THE INVENTION

[0002] This invention is for application within the industry dedicatedto the distribution of electrical energy, to be precise withinelectrical networks with large voltage drops.

BACKGROUND OF THE INVENTION

[0003] Problems with the regulation of voltage in electrical energydistribution networks are customary, as is the implantation of equipmentwith the aim of mitigating the problem.

[0004] Worth mentioning is the embodiment as auto-transformers withintake points, controlled by static or mechanical switches, as well asthe use of motorised, continuously regulated auto-transformers.

[0005] This equipment performs the function required of them, but at theprice of a large economic investment and/or a considerable reduction insupply reliability.

[0006] For its part the applicant is unaware of the current existence ofany voltage stabiliser for electrical energy transportation anddistribution applications that is designed to be implanted in electricalnetworks with large voltage drops and which presents the same featuresas the one described in this specification.

DESCRIPTION OF THE INVENTION

[0007] The voltage stabiliser for electrical energy transportation anddistribution applications proposed by the invention constitutes initself an evident innovation within its field of application.

[0008] To be more precise, the voltage stabiliser for electrical energytransportation and distribution applications takes the form of a voltagestabiliser for electrical energy transportation and distributionapplications, admitting of installation in single phase and three phasenetworks, consisting of one or several electromagnetic devices oftransformer type and which, in incremental steps, regulates the outputvoltage which reaches the consumers.

[0009] The basic regulation device consists of a transformer with aprimary dual or quadruple winding, and with a simple secondary winding,prepared to withstand the line's full intensity.

[0010] The simple winding may be positioned before or after the parallelbranch, the performance of the equipment remaining the same.

[0011] With the aid of the appropriate commutation of the primarywindings, corrections are made to the output voltage, with the purposeof keeping it within pre-set margins.

[0012] This basic element offers features of very considerable economy,robustness and efficacy, the output discretisation being five ornine-step, which makes the invention of interest to installations wherethere is a major problem of voltage regulation and where a coarseregulation is required at around the nominal voltage value.

[0013] Nevertheless, should greater resolution be needed, the inventionadmits the use of devices in series, with regulations stepped 4:1.

DESCRIPTION OF THE DRAWINGS

[0014] In order to complement the herein description, and with the aimof assisting in the better understanding of the invention'scharacteristics, attached to the herein specification, and forming anintegral part of it, is a set of plans in which, by way of illustrationand in no way limiting, the following has been depicted:

[0015]FIG. 1.—offers a graphic representation of the single phase schemeequivalent of the equipment's power circuit and shows, to be moreprecise, the downstream compensation which allows the main transformer'spower to be reduced, at the price of not exploiting to the full themagnetic circuit at non-nominal voltages. FIG. 1 corresponds to theobject of the invention relating to a voltage stabiliser for electricalenergy transportation and distribution applications.

[0016]FIG. 2.—offers a view similar to that shown in FIG. 1, exploitingto the full the magnetic circuit at non-nominal voltages as aconsequence of upstream compensation.

PREFERRED EMBODIMENT OF THE INVENTION

[0017] The voltage stabiliser for electrical energy transportation anddistribution applications which is being proposed and which isspecifically designed for electrical energy transportation anddistribution applications, may be embodied for a single phase or threephase network. The elements specified are those used in the single phaseequipment, but it should be pointed out that the construction of thethree phase stabiliser is immediate given that all that is needed is totriplicate the equipment if one control per phase is desired, or totriplicate the number of contactor and relay poles, should a jointcontrol be desired.

[0018] As may be seen in FIGS. 1 and 2, there are two variants of thesingle phase scheme equivalent of the equipment's power circuit, thedifference as shown between both residing in the fact of whether theline compensation is before or after the parallel branch.

[0019] The downstream compensation, shown in FIG. 1, allows the maintransformer's power to be reduced, at the price of not exploiting to thefull the magnetic circuit at non-nominal voltages. There is fullexploitation in upstream compensation, the scheme for which is shown inFIG. 2.

[0020] The voltage stabiliser for electrical energy transportation anddistribution applications is composed of a transformer,trip/contactor/relay elements and a control panel.

[0021] The transformer takes the shape of a transformer whose primaryvoltage is the same as the line's nominal single phase voltage (Vfn), asreferred to in the figures mentioned above, and whose secondary voltageis the same as the maximum voltage increase that it is wished to injectinto the line (Viny), also to be seen in the figures.

[0022] The primary winding is coiled double in two electromagneticallyidentical coils. This enables it to be connected at the 2*Vfn/vinyconnection too.

[0023] In the case of downstream compensation, as shown in FIG. 1, thepower of this machine will be Viny*Ilinea, where Ilinea is the nominalcurrent of the line on the stabilised side. In the case of upstreamcompensation, the scheme for which is shown in FIG. 2, the power of thismachine will be Viny*Ilinea (1+Viny/Vfn), albeit the services ofcompensation provided are higher.

[0024] With respect to the trip/contactor/relay elements, it should bepointed out that the equipment requires a power-cutting element (C1)with one normally closed contact (NC) and another normally open (NO), ata nominal line current.

[0025] In addition two isolator elements (R1 and R2) are needed, each ofwhich is provided with two normally open contacts and two normallyclosed contacts (NO and NC respectively) , with a nominalV_(fn)/V_(iny), the current of the line These two elements may besubstituted by static cutting elements.

[0026] As for the control panel, it should be pointed out that itconsists of a microprocessor which measure the output voltage and sendsthe orders to the trip, contactor and relay elements, in order that theyare correctly configured for adjusting the voltage within limits.

[0027] As for the mode of operation, it should be pointed out that theconfiguration of the contactors as shown in FIG. 1 allows for fivepossible manoeuvres to be carried out. Namely:

[0028] With C1, that is to say the power cutting elements, at rest andthe isolator elements in any position, the equipment is physicallydisconnected from the network. It should be pointed out that this modeof operation allows the continuity of the supply to be guaranteed in theface of a failure in the equipment, as well as avoiding the introductionof losses in the non-stabilisation situation.

[0029] With C1 activated and the two isolator elements at rest, theregulator multiplies the input voltage by (1+0.5*V_(fn)/V_(iny)). Innominal conditions this means an injection of +0.5*V_(fn)/V.

[0030] With C1 and R1 activated and R2 at rest, the regulator injectsinto the network a voltage of +V_(iny) V in nominal conditions.

[0031] With C1 and R2 activated and R1 at rest, the regulator injectsinto the network a voltage of −0.5 V_(iny) V in nominal conditions.

[0032] With C1, R1 and R2 activated, the regulator injects into thenetwork a voltage of −V_(iny) V in nominal conditions.

[0033] That is to say, C1, to be precise the power cutting element,connects the equipment, while one isolator element (R1) determines themagnitude of the trip (0.5*V_(iny) or V_(iny)) and the other isolatorelement (R2) determines the configuration's polarity (+/−).

[0034] The control of the basic element measures in network cycle realtime the effective values of the equipment's output voltages, thuspermitting them to be stabilised within a margin of[V_(fn)+/−V_(iny)/4], provided that the input voltage lies within theinterval [V_(fn)+/−V_(iny)/4].

[0035] The voltage compensation manoeuvres are carried out in line withthe following process, namely:

[0036] 1.—Deactivation of C1.

[0037] 2.—With the aid of C1's auxiliary contact, verification that themanoeuvre was carried out correctly.

[0038] 3.—Activation/deactivation of R1 and R2 (manoeuvre withoutvoltage or current).

[0039] 4.—Activation of C1.

1. Voltage stabiliser for electrical energy transportation anddistribution applications, of the kind designed for use as a voltagestabiliser for electrical energy transportation and distributionapplications, able to be installed in single phase and three phasenetworks, consisting of one or several devices of transformer type,which in incremental steps regulates the output voltage that reaches theconsumer, characterised in that it comprises a transformer,trip/contactor/relay elements, and a control panel, the transformertaking the form of a transformer of primary voltage similar to thenominal single phase line voltage (Vfn) and of secondary voltage equalto the maximum voltage increase it is wished to inject into the line(Viny), the primary winding being double wound in twoelectromagnetically identical coils, including a power-cutting element(C1) with one normally closed contact and one normally open, having anominal current corresponding to the nominal current of the line andincorporating two isolator elements (R1 and R2), each of which isprovided with two normally open contacts and two that are normallyclosed, with a nominal current of V_(fn)/V_(iny), the current of theline and having a control panel composed of a microprocessor thatmeasures the output voltage and sends the orders to the trip, contactorand relay elements.
 2. Voltage stabiliser for electrical energytransportation and distribution applications, according to the firstclaim, characterised in that the isolator elements R1 and R2 may besubstituted by static trip elements.
 3. Voltage stabiliser forelectrical energy transportation and distribution applications,according to the first claim, characterised in that the stabiliser maybe embodied for a three phase network by triplicating the equipment. 4.Voltage stabiliser for electrical energy transportation and distributionapplications, according to the first and the third claims, characterisedin that the stabiliser may be embodied for a three phase network bytriplicating the number of contactor and relay poles for their jointcontrol.
 5. Voltage stabiliser for electrical energy transportation anddistribution applications, characterised in that the primary winding isdouble wound in two electromagnetically identical coils, thus permittingits connection at the 2*Vfn/Viny connection, giving a power in the caseof downstream compensation of Viny*Ilinea, where Ilinea is the nominalline current on the stabilised side.
 6. Voltage stabiliser forelectrical energy transportation and distribution applications,according to the first and the fifth claims, characterised in that theupstream compensation gives a stabiliser power of Viny*Ilinea(1+Viny/Vfn).
 7. Voltage stabiliser for electrical energy transportationand distribution applications, according to the preceding claims,characterised in that it is endowed with a transformer with a primarywinding provided with two or four coils, which may be connected inseries, in parallel or in series and parallel.
 8. Voltage stabiliser forelectrical energy transportation and distribution applications,according to the first and the seventh claims, characterised in that itincorporates a charge cutting element and two isolator elements fordisconnecting the primary and short-circuiting the secondary.